Xen Hypervisor OOB read/write via vCPU mask hypercalls
CVE-2025-58148 Published on October 31, 2025
x86: Incorrect input sanitisation in Viridian hypercalls
[This CNA information record relates to multiple CVEs; the
text explains which aspects/vulnerabilities correspond to which CVE.]
Some Viridian hypercalls can specify a mask of vCPU IDs as an input, in
one of three formats. Xen has boundary checking bugs with all three
formats, which can cause out-of-bounds reads and writes while processing
the inputs.
* CVE-2025-58147. Hypercalls using the HV_VP_SET Sparse format can
cause vpmask_set() to write out of bounds when converting the bitmap
to Xen's format.
* CVE-2025-58148. Hypercalls using any input format can cause
send_ipi() to read d->vcpu[] out-of-bounds, and operate on a wild
vCPU pointer.
Vulnerability Analysis
CVE-2025-58148 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a high impact on confidentiality, with no impact on integrity and availability.
Weakness Types
Out-of-bounds Read
The software reads data past the end, or before the beginning, of the intended buffer. Typically, this can allow attackers to read sensitive information from other memory locations or cause a crash. A crash can occur when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string. The expected sentinel might not be located in the out-of-bounds memory, causing excessive data to be read, leading to a segmentation fault or a buffer overflow. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent read operation then produces undefined or unexpected results.
What is a Memory Corruption Vulnerability?
The software writes data past the end, or before the beginning, of the intended buffer. Typically, this can result in corruption of data, a crash, or code execution. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent write operation then produces undefined or unexpected results.
CVE-2025-58148 has been classified to as a Memory Corruption vulnerability or weakness.
Products Associated with CVE-2025-58148
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Affected Versions
Xen Version consult Xen advisory XSA-475 is unknown by CVE-2025-58148Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.